An iridium(III) complex based luminogenic probe for high-throughput screening of H2S donors in living cells

Abstract The scarcity of suitable high-throughput screening technology for H₂S donors has hampered the discovery of H₂S donors. In this study, a long-lived cyclometalated iridium complex was rationally designed as a mitochondria-targeted H₂S probe to monitor the real-time dynamic change of H₂S. By using time-resolved emission spectroscopy (TRES) technique, an anti-interference high-throughput screening system was developed to monitor H₂S in living cells with decreased false negative results. As a proof-of-concept, three natural products were identified as potential H₂S donors from a natural product library using the developed TRES probe. Notably, the discovery of allicin and diallyl trisulfide demonstrated the feasibility of this screening platform, while garlic derived allyl methyl sulfide was explored as a H₂S donor candidate. The results were further validated by a commercial assay. We anticipate this high-throughput platform could facilitate the discovery of H₂S donors by discriminating the endogenous interfering fluorescence from biological system.